make sure to try out the free trial before you buy (you're limited to a few minutes of audio at a time) to see if it will work for you.
it will also stream to a free program that has versions for windows, mac and linux.

this delay is always in airtunes, iTunes just makes the interface match the delayed audio. to see this play a track and hit next song. do it both in local only, and out of airtunes speakers, and you'll see a difference in the speed at which the track changes.

if you're only using it for audio (like last.fm or pandora) and not video (like youtube) it will be perfect.

for last.fm look at sweet.fm it's a stand alone client, so you don't have to worry about catching other audio from your browser. It's also a bit more flexible as you can type "/a band" for a certain band's radio or "/u name" for a certain user's library. there are other options.

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